66611356020 has 960 divisors, whose sum is σ = 256706537472. Its totient is φ = 14266368000.

The previous prime is 66611356001. The next prime is 66611356057. The reversal of 66611356020 is 2065311666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 319 ways as a sum of consecutive naturals, for example, 385036654 + ... + 385036826.

Almost surely, 2^66611356020 is an apocalyptic number.

66611356020 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66611356020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (128353268736).

66611356020 is an abundant number, since it is smaller than the sum of its proper divisors (190095181452).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66611356020 is a wasteful number, since it uses less digits than its factorization.

66611356020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294 (or 283 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

Adding to 66611356020 its reverse (2065311666), we get a palindrome (68676667686).

The spelling of 66611356020 in words is "sixty-six billion, six hundred eleven million, three hundred fifty-six thousand, twenty".